The Coast Guard continues to search for four fishermen missing for nearly two days in the Gulf of Mexico.

The Coast Guard received a distress signal from the 50-foot vessel at 3:30 a.m. Friday, Petty Officer Richard Brahm said. The boat began sinking about 115 miles southeast of Galveston, not far from the Texas-Louisiana border.

Weather conditions were bad at the time, Brahm said. Sustained winds were strong, at 33 mph, and there were gusts of up to 40 mph, he said. The water was 50 degrees, and sea swells were between 10 feet and 15 feet, which was enormous for the 50-foot boat the men were in, he added.

About five hours after the distress signal, at 8:30 a.m., a search team found crew member John Reynolds on a life raft. Reynolds was flown to Ellington Airport and returned to Galveston later Friday. He told the Coast Guard he was unsure what had happened to the other four fishermen that were on board, Brahm said.

Overnight, the Coast Guard used one cutter and one aircraft to search an area slightly smaller than the state of Delaware. They added two more aircraft to the hunt at daybreak Saturday, Brahm said.

"We're going to keep searching until someone tells us to stop," he said, noting that the Coast Guard uses a variety of factors to determine whether there is a possibility the men could still be alive.

Brahm said the Coast Guard would continue searching through Saturday night.

The Associated Press contributed to this report ___________________________________________________________